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Grating couplers are one of the most significant elements for the coupling of light between optical fibers and photonic integrated circuits. In this paper, we present the design, fabrication and experimental characterization of Silicon on Insulator (SOI) based grating couplers. The mode matching of diffracted optical field from the grating coupler with a single mode fiber at different angles is investigated here with normal surface physical contact (PC) and angled physical contact (APC) fibers. According to our simulations, the 1°tilt in the fiber angle approximately changes the position of the optimum mode coupling for the grating coupler with the single mode fiber by ∼ 300 nm distance. The variation of input wavelength at different grating periods gives the different optimal coupling angles for the PC fibers. The experimental results also demonstrate the coupling efficiency as −3.6 dB at 1550 nm with a simulated 3-dB bandwidth of 48 nm near the telecommunication C-band.

Purpose/Objective(s) To compare the outcomes of upfront (chemo)radiotherapy ((CC)RT) versus surgery in early stage human papilloma virus-positive oropharyngeal squamous cell carcinoma (hpv+OPC), and investigate for preoperative clinical factors that can predict eventual requirement for postoperative (CC)RT. Materials/Methods A multicenter retrospective study including 166 patients with histologically proven AJCC 8th ed. stage I–II hpv+OPC was conducted. We excluded patients who received induction chemotherapy (CT) and adjuvant cetuximab CT. Patients who didn't receive concurrent cisplatin–based CT with a single lymph node (LN) > 3cm or multiple LNs were also excluded from the analysis. As a result, sixty (36.1%) and one-hundred six (63.9%) patients received upfront (CC)RT and surgery, respectively. Seventy-eight (73.6%) patients in the upfront surgery group received postoperative (CC)RT. Results With a median follow-up of 45.1 months, the 2-year overall survival (OS), progression free survival (PFS) and locoregional control (LC) for (CC)RT/surgery were 97.8%/96.4% (P = 0.755), 91.1%/92.0% (P = 0.810) and 92.9%/93.3% (P = 0.721), respectively. In multivariate analyses, patients showing synchronous radiologic extranodal extension and conglomeration (ENEcong) of metastatic LNs showed significantly poor OS (P = 0.047), PFS (P = 0.001) and LC (P = 0.003). In patients undergoing upfront surgery, the number of clinically positive LN ≥2 (OR, 5.15; P = 0.004) and LN with ENEcong (OR, 3.75; P = 0.009) were predictors of postoperative CCRT. No patient in the (CC)RT group demonstrated late severe toxicity whereas 3 (2.8%), 1 (0.9%), and 1 (0.9%) patient in the surgery group showed grade 3 dysphagia, grade 3 xerostomia, and fatal oral cavity bleeding. Conclusion We found no differences in OS, PFS, and LC between (CC)RT vs. surgery as initial treatment in stage I–II hpv+OPC which warrants comparison via a prospective trial in the treatment de-escalation era. However, most patients undergoing upfront surgery needed adjuvant (CC)RT. Pretreatment findings of LN metastases are prognostic as well as predictive for the need of adjuvant treatment.

This paper proposes a high-efficient and fast-transient buck-boost DC-DC converter for battery-powered mobile devices. The proposed converter employs an adaptive direct path skipping to minimize the switching losses caused by power transistors, and thus enhances the power efficiency and extends the usage time of the mobile device. It also adopts an on-duty modulation to achieve a fast line transient response, thereby rapidly regulating its output voltage. The proposed buck-boost converter was fabricated using 0.18-μm CMOS process technology with 1.8 V and 6.0 V CMOS devices. The measurement results show that the maximum power efficiency is achieved up to 97.6% at a load current of 100 mA. In addition, the measured line transient response is 155 μs/V.

A composite railroad track is a rigid track system that is developed using quick-hardening infilling materials, and has the advantages of a reduced maintenance cost compared to a conventional ballasted track. Quick-hardening infilling materials were developed in this study, which does not require the processes of cleaning the aggregates crushed due to the repeated load imposed by rolling stock, and thus the materials can strengthen existing ballasted tracks with an enhanced level of efficiency and speed. Theoretical reviews of pore size, permeability, pore channel length and tortuosity depending on the size of the aggregate in ballasted tracks were conducted first to predict the influence of filling parameters of infilling materials for composite railroad tracks. Based on the theoretical filling performance analysis of ballasted tracks, a thermosetting polymer was developed, which is a 3D cross linking agent that performs redox radical polymerization reaction at room temperature. The polymer was used as a primary filling material to fill the lower ballast layer, which could not be filled by conventional cement-based filling materials. A double-layered composite was formed by filling the upper ballast layer with the ceramic-based secondary filling material using the reaction between dead-burned magnesia and acid ammonium phosphate. The performance of infilling materials was validated through strength measurement and microscopic analysis.

With the evolution of state-of-the-art applications and paradigms, the world is progressing toward smart cities. Smart homes are an important aspect of smart cities, wherein various mobile computing and network technologies are used. However, they are also susceptible to security threats that can cause serious issues related to privacy and safety. Z-Wave is a wireless technology primarily used in smart homes; however, its protocol has not been sufficiently investigated. In this study, we examined threat modeling for the Z-Wave protocol to determine the security issues and suggested attack scenarios in which we gained full control over the commercial products that implement Z-Wave. We analyzed the level 2 data flow diagram of actual products. The experimental results revealed that the major products that implement Z-Wave have several vulnerabilities. A video demonstrating our experimental result can be found at https://youtu.be/sM-NlJexDPU .

Background Oropharyngeal squamous cell carcinoma (OPSC) continues to increase in incidence with human papillomavirus (HPV) infection. Despite the good overall prognosis, it needs to assess the risk of not only survival, but also the risk of local, regional, or distant treatment failure to guide de-intensification regimens. This study aimed to investigate the expression of estrogen receptor (ER) and programmed cell death-ligand 1 (PD-L1) proteins according to the status of HPV infection and their prognostic implication in OPSCC patients. Methods Consecutive 80 patients diagnosed with OPSCC with surgical treatment from 2004 to 2017 were included. Immunohistochemistry for ER and PD-L1 was performed formalin-fixed, paraffin embedded tissues. HPV status assessed with p16 immunohistochemistry and HPV DNA testing. Results ER and PD-L1 expression were observed in 37.5% (30/80) and 60% (48/80), respectively. Both ER and PD-L1 protein expression were higher in HPV-positive OPSCC than in HPV-negative subgroup (47.5% vs. 9.5% for ER, 66.1% vs. 42.9% for PD-L1). There was no significant association between ER and PD-L1 expression (correlation coefficient: 0.105, p > 0.05). Using Kaplan-Meier curves, PD-L1 expression was associated with longer recurrence-free duration (p = 0.013), whereas ER expression was associated with prolonged overall survival (p = 0.043). In subgroup analysis, PD-L1 expression was found to be an independent excellent prognostic factor for recurrence-free duration in HPV-positive OPSCC (p = 0.002, HR = 0.085 [0.018-0.399]). ER expression also tended to be associated with longer overall survival in the HPV-positive OPSCC subgroup, but no statistical significance was observed. In HPV-negative subgroup, both ER and PD-L1 expression were not associated with any clinicopathologic factor nor survival. Conclusions ER and PD-L1 expression can be complementary prognostic factors in HPV-positive OPSCC. It may allow us to investigate the independent role of anti-hormone receptors and the tumor microenvironment in the treatment of OPSCC. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

In 2007, a genome-wide association study identified associations between variants involved in the regulation of ORMDL3 expression and asthma. These observations were subsequently replicated in case-control studies in several ethnic groups. We investigated the possible contribution of GSDMB/ORMDL3 variants to asthma susceptibility and intermediate asthma phenotypes in Korean children. The polymorphisms rs7216389, rs4794820, rs4065275, and rs11650680 were genotyped using the TaqMan assay in 931 asthmatics and 480 normal controls in a case-control study, and in 1907 elementary school children in a general population study. Each subject also underwent peripheral blood analysis of immunoglobulin E levels, eosinophil cationic protein (ECP) levels, and eosinophil percentage. Pulmonary function testing (FEV(1) and MMEF) and a methacholine provocation test (PC(20)) were also performed. The case-control study revealed a significant association between a linkage disequilibrium block, including rs7216389, rs4794820, and rs4065275, and susceptibility to asthma and atopic asthma. The CT and TT genotypes of rs11650680 were associated with lower logECP levels than the CC genotype in asthmatics, while the GA and AA genotypes of rs4794820 were associated with higher logPC(20) values than the GG genotype in atopic asthmatics. The haplotype (CAA) of rs7216389, rs4794820 and rs4065275 was associated with a lower risk of asthma susceptibility and a higher logPC(20). In the general population study, rs11650680 was significantly associated with a diagnosis of asthma. Moreover, the GA and AA genotypes of rs4794820 were associated with higher logPC(20) values and lower eosinophil percentages than the GG genotype in subjects who had been diagnosed with asthma, or showed bronchial hyperresponsiveness (PC(20)≤16). The GSDMB/ORMDL3 gene block, which includes rs7216389, rs4065275, rs4794820, and rs11650680, may be associated with asthma susceptibility in Korean children because it promotes eosinophilic inflammation, which induces bronchial hyperresponsiveness.

This study proposes an optimization cutting speed program developed to improve the machining precision and tool life in high speed machining using the ball end mill. This program optimizes the cutting speed that varies during free surface machining. As for the technique of optimization cutting speed, the NC code generated from CAD/CAM goes through a reverse post process and cutting simulation and the effective tool diameter of the ball end mill is obtained. Then the range of critical cutting speed suitable for the workpiece is selected and the spindle revolution is changed according to the effective tool diameter within the range of the critical cutting speed. In this paper, the machining precision and tool life were compared in the free surface machining conducted by the general cutting method and the technique of optimization cutting speed.

M O N D A Y 574 Age-Dependent Cut Points for Airway Hyperresponsiveness to Distinguish Asthma from Healthy Children in Methacholine Challenge Test Ji-Won Kwon, MD, Eun Lee, Song-I. Yang, MD, Young-Ho Ho Jung, MD, Ju-Hee Seo, MD, Byoung-Ju Kim, MD, PhD, Hyo-Bin Kim, MD, PhD, So Yeon Lee, MD, PhD, Woo Kyung Kim, MD, PhD, Jung Yeon Shim, MD, PhD, Soo-Jong Hong, MD, PhD; Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, South Korea, Department of Pediatrics, Childhood Asthma Atopy Center, Research Center for Standization of Allergic Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea, Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea, South Korea, Department of Pediatrics, Korea Cancer Center Hospital, Seoul, South Korea, Department of Pediatrics, Hae-undae Paik Hospital, Inje University College of Medicine, Busan, South Korea, Department of Pediatrics, Inje University Sanggye Paik Hospital, Seoul, South Korea, Department of Pediatrics, Hallym University College of Medicine, Seoul, South Korea, Research Center for Standardization of Allergic Diseases, Seoul, South Korea, South Korea, Department of Pediatrics, Seoul Paik Hospital, Inje University College of Medicine, Seoul, South Korea, Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University College of Medicine, Seoul, South Korea. RATIONALE: Cut-off points of bronchial provocation tests to distinguish asthma in children have not been fully investigated. We evaluated agedependent cut-off values of bronchial provocation test to determine asthma in children. METHODS: A total of 3,045 subjects aged from 6 to 19 years old were undertaken a methacholine challenge test. All subjects were classified into 3 groups. The group 1 included patients with clinical asthma diagnosed by pediatric allergist. The group 2 included 280 subjects with a history of recent wheeze, physician diagnosed asthma, or recent asthma treatment by a Korean version of ISAAC questionnaire from population-based researches. The group 3 included healthy subjects (n52,399) except group 2 from population studies. Receiver operating characteristics curves to determine the cut-off values for clinical asthma were analyzed between group 1 and 3, and also analyzed between group 2 and 3. RESULTS: From ROC analysis between group 1 and 3, cut-off values for determining asthma were increased with age. Cut-off of PC20 were 5.95 mg/ml at age 6, 9.13 mg/ml at age 7, 11.77 mg/ml at age 8, 12.62 mg/ml at age 9, 14.94 mg/ml at age 10, 16.61 mg/ml at age 11, and 24.60 mg/ ml at age more than 15 years. All cut-off points were statistically significant. In ROC analysis between group 2 and 3, a significant cut-off value was only found in subjects aged more than 15 years. CONCLUSIONS: The reference values of PC20 for determining asthma distinguished from healthy children were increased with age. Age-dependent interpretation is needed in evaluating AHR in children with asthma.

Background Antibiotic use in infancy induces alteration in intestinal microbiota and is associated with the development of allergic diseases. Mold exposure is also associated with allergic diseases. Genetic susceptibility may interact with specific environmental factors in allergic disease development. Objective To investigate independent and combined effects of antibiotic use and mold exposure in infancy on the risk of allergic rhinitis (AR) in adolescents. Methods Data on AR and environmental factors were collected using the International Study of Asthma and Allergies in Childhood questionnaire from 7,389 adolescents from Seoul, Korea. TaqMan genotyping was performed for interleukin 13 (IL-13) (rs20541) and Toll-like receptor 4 (rs1927911) polymorphisms in 1,395 adolescents. Results Age, parental history of AR, antibiotic use in infancy, and pet ownership during pregnancy or infancy were associated with an increased risk of current AR (diagnosis of AR and symptoms of AR within the preceding 12 months). Having older siblings was a protective effect. The adjusted odds ratio (aOR) for current AR for combined antibiotic use and mold exposure in infancy was 1.45 (95% confidence interval [CI], 1.01–2.09). For each factor separately, aORs were 1.25 (95% CI, 1.04–1.50) and 0.99 (95% CI, 0.75–1.31), respectively. Antibiotic and mold exposure in infancy, GA or AA genotypes of IL-13 (rs20541) (aOR 4.53; 95% CI, 1.66–12.38; P for interaction = .05), and CT+TT genotype of Toll-like receptor 4 (rs1927911) (aOR, 3.20; 95% CI, 1.24–8.26; P for interaction = .18) increased the risk of current AR. Conclusion Antibiotic use and mold exposure in infancy have additive effects on the risk of current AR in genetically susceptible adolescents. Gene-environment interactions between IL-13 (rs20541) and antibiotics or mold may play a role in AR.

E S D A Y 983 Effect Of Prenatal Exposure To Indoor PM2.5 and Environmental Tobacco Smoke Affecting Lower Respiratory Tract Infection Was Modified By ROS Genes: Cocoa Study Dr. Song I. Yang, MD, Dr. Eun Lee, MD, Dr. Young Ho Jung, MD, Kil-Yong Choi, Mi-Jin Kang, MS, Ho-Sung Yu, Cheol Min Lee, Prof. Youn Ho Shin, MD, PhD, Prof. Kangmo Ahn, MD, PhD, Prof. Kyung Won Kim, MD, PhD, Prof. Soo-Jong Hong, MD, PhD Cocoa study Group; Childhood Asthma Atopy Center, Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea, Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul, South Korea, Institute of Environmental and Industrial Medicine, Hanyang University, Seoul, South Korea, Department of Pediatrics, CHAMedical Center, CHAUniversity College of Medicine, Seoul, South Korea, Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea, Department of Pediatrics, Yonsei University College of Medicine, Seoul, South Korea, COCOA study group. RATIONALE: Prenatal air pollution exposure associates with impaired fetal growth, decreased lung function, respiratory morbidity and mortality. We aimed to investigate the influence of prenatal indoor fine particulate matter (PM2.5) and environmental tobacco smoke (ETS) exposure and genetic polymorphisms on the susceptibility to respiratory tract infection (RTI) in infancy. METHODS: Demographic, environmental factors and diagnosis of RTI in the first year of life were evaluated in 231 infants from a birth cohort of general population in Korea between 2007 and 2011. Indoor PM2.5 was measured during the third trimester and mothers were asked about ETS exposure during pregnancy. Nuclear factor (erythroid-derived 2)-like 2 (NRF2, rs6726395), glutathione S-transferase pi 1 (GSTP1, rs1695) and glutathione S-transferase mu 1 (GSTM1, copy number variation) genotyping was performed. RESULTS: Prenatal indoor PM2.5 or ETS exposure increased the risk of bronchiolitis and lower RTI (LRTI), but not upper RTI (URTI), in infancy. They also synergistically increased susceptibility to bronchiolitis and LRTI (aOR 5.20; 95% CI 1.10-24.61, aOR 5.18; 95% CI 1.40-19.24, respectively), but not URTI. This synergistic effect was increased by Nrf2 GG (aOR10.23; 95%CI 1.02-102.57, aOR 14.01; 95%CI 1.42-138.02, respectively) and GSTM1 null genotypes (aOR 9.45; 95% CI 1.03-86.78, aOR 5.70; 95% CI 1.02-31.95, respectively). CONCLUSIONS: Indoor PM2.5 and ETS exposure during the prenatal period synergistically increased susceptibility to bronchiolitis and LRTI, but not URTI. This effect was modified by polymorphisms in reactive oxygen species-related genes.

Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center, Ulsan University College of Medicine, Seoul, Korea Department of Pediatrics, CHA University School of Medicine, Seongnam, Korea Research Center for Standardization of Allergic Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea Department of Pediatrics, Kosin University Gospel Hospital, Kosin University College of Medicine, Busan, Korea Department of Pediatrics, Korea Cancer Center Hospital, Seoul, Korea Department of Pediatrics, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seoul, Korea Department of Pediatrics, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea Department of Pediatrics, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, Korea Department of Pediatrics, Hallym Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea Department of Pediatrics, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea Department of Pediatrics, Seoul Paik Hospital, Inje University College of Medicine, Seoul, Korea Department of Pediatrics, National Health Insurance Corporation Ilsan Hospital, Seoul, Korea Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea

Background Recent studies have identified an increase in the prevalence of asthma associated with paracetamol use. Objective To identify the relationship among asthma, biomarkers, genes, and paracetamol use in preschool children. Methods We undertook a population-based, cross-sectional survey of 933 preschool children. Asthma status was classified according to medical history and asthmatic symptoms. History of paracetamol use in infancy was recorded. Impulse oscillometry, blood tests for eosinophils and total IgE, and genotyping of NAT2 , Nrf2 , and GSTP1 polymorphisms by TaqMan assay were conducted. Result Paracetamol use in infancy was associated with an increased risk of treatment for asthma within the previous 12 months. Paracetamol use together with a family history of asthma increased the risk of asthma diagnosis ever, current asthma, and treatment for asthma within the previous 12 months. Gene polymorphisms in NAT2 (rs4271002), Nrf2 (rd6726395), and GSTP1 (rd1695) increased the risk of treatment for asthma within the last 12 months. Eosinophils were significantly elevated in the group with paracetamol use and a family history of asthma; however, the serum total IgE level and IOS did not show any significant difference. Conclusion Paracetamol use in infancy was significantly associated with increased risk of asthma. The association is more significant in genetically susceptible children, related to antioxidant genes, and the effect may be mediated by eosinophilic inflammation.

Purpose Confident reconstruction of palatal defect by radial forearm fasciocutaneous free flap. Methods A 67 year male patient who had total palate defect including hard palate after the ablative surgery of adenoid cystic carcinoma originating from soft palate were immediately reconstructed using radial forearm fasciocutaneous free flap to restore nasal and oral separation. Vascular anastomoses were done with facial vessels in neck and the donor site was closed with split thickness skin graft. All suture wounds in the oral and nasal side had healed primarily without complication till the postoperative 14th day. But the disruption of wounds and downward prolapsed of flap was noticed in the oral cavity during the follow-up session and it required revisional operation. During the revisional operation, a prefabricated temporal palatal obturator for the protection of the repair wounds and the anti-gravitational support was applied beneath the flap. Results After applying palatal obturator, no more disruption was reported in the additional follow-ups. The patient was then able to swallow soluble foods in the 3 weeks postoperatively and prepare the further radiation therapy. The temporary palatal obturator was safely removed 6 weeks after revisional operation. Conclusion Radial forearm fasciocutaneous free flap is versatile for soft tissue reconstruction of palate which provides a satisfactory separation between oral and nasal cavity. But it can be prolapsed down due to gravity and its bulk and this makes disruption of the wound during early postoperative period. The temporary palatal obturator was a good answer to sustain the flap in place until secure implantation.